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1.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1989,92(3):487-492
- 1.1. Subcellular distribution of (NA+, K+-ATPase and ouabain-insensitive ATPase (Mg2+-ATPase) are compared in branchial tissues of the euryhaline crab, Eriocheir sinensis, acclimated to fresh water.
- 2.2. Both the anterior and posterior gills contain cAMP-dependent protein kinase and endogenous protein substrate for phosphorylation.
- 3.3. Phosphorylation occurs in both “particulate” and “soluble” subcellular fractions but its stimulation by cAMP is restricted to the “soluble” fraction.
- 4.4. serotonin (5-HT) and dopamine receptors are present only in the “light particulate” fraction isolated from the posterior gills.
- 1.(a) Serotonin and dopamine have no effect on the phosphorylation observed in a subcellular fraction alone.
- 2.(b) Activation of the phosphorylation by serotonin and dopamine is found when the soluble fraction (source of cAMP-dependent protein kinase) is added to the fraction P3 from the posterior gills.
- 3.(c) No activation occurs with the fractions P3 as well as P1 or P2 (not shown) from anterior gills of fresh water crab.
- 4.(d) Cyproheptadine, a serotonin receptor antagonist, inhibits the 5-HT dependent increase in phosphorylation.
- 5.(e) The dopamine receptor antagonist, chlorpromazine, inhibits dopamine-stimulated phosphorylation.
- 6.5. Ouabain mimics the effect of cyproheptadine on the serotonin-stimulated phosphorylation found in the posterior gills.
2.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1981,68(2):359-366
- 1.1. DEAE-cellulose chromatography of mycelial alkaline phosphatase (orthophosphoric monoester phosphohydrolase, EC 3.1.3.1) from Basidiobolus haptosporosus, produced three iso-enzymes “A”, “B” and “C”.
- 2.2. Fraction “A” was further characterized and showed maximum activity at pH 10 in 0.1 M sodium carbonate-bicarbonate buffer.
- 3.3. The enzyme was stimulated by Mg2+, Co2+ and Mn2+ and inactivated by Zn2+, Cu2+, EDTA, citrate and tartrate.
- 4.4. Phosphate ions inhibited it competitively, phenylalanine uncompetitively and urea noncompetitively.
- 5.5. It was heat stable for 60 min at 37°C but labile above 55°C.
- 6.6. Its Km with p-nitrophenylphosphate was 0.5 mM; its estimated molecular weight was 160,000.
- 7.7. The results are compared with the properties of alkaline phosphatases from the rainbow lizard and man and discussed in terms of a triadic association between the fungus, the lizard and man.
3.
《Comparative biochemistry and physiology. A, Comparative physiology》1992,101(1):131-136
- 1.1. The ontogeny of type I and type III deiodinase activities was studied in embryonic and posthatch chicks.
- 2.2. Hepatic type I activity showed a 3-fold increase up to the period of pipping and hatching and decreased slowly thereafter.
- 3.3. Hepatic type III activity increased by 3-fold from E14 to E17 and decreased more than 10-fold from E17 to CO. Posthatch levels were very low.
- 4.4. Type I activity in the kidney decreased slowly after hatching while type III activity was very low over the whole period studied.
- 5.5. Developmental changes during the late embryonic period suggest a causal relationship between the increase in plasma GH and T3 levels and the decrease in hepatic type III activity.
4.
《The International journal of biochemistry》1993,25(4):525-532
- 1.1. When acute liver damage is induced in rats treated with CCl4, both prothrombin biosynthesis and gamma carboxylase activity decreases, originating a prolongation of prothrombin time in plasma.
- 2.2. Then, during the regenerative process, prothrombin biosynthesis increases higher than normal, but gamma carboxylase activity remain decreased. In this case, prolongation of prothrombin time occurs in spite of high levels of descarboxylated prothrombin in plasma.
- 3.3. An increase of descarboxylated prothrombin in plasma is also detected in the CCl4-liver fibrosis model.
5.
《Comparative biochemistry and physiology. A, Comparative physiology》1991,98(3):563-569
- 1.1. Two kinds of neurons were identified in the body-wall longitudinal muscle layer of the earthworm, Amynthas hawayanus, by the simultaneous potential recording and Lucifer Yellow-CH injection method with a single microelectrode.
- 2.2. Both kinds of neurons have their somata, neuntes and longitudinal processes imbedded in the longitudinal muscle layer. Those with two circular processes extending into the third segmental nerve trunk are tentatively named “intra-nerve-trunk” neurons and those with four circular processes extending into four setae shafts are tentatively named “intramural” neurons.
- 3.3. Both kinds of neurons responded to electrical and mechanical stimuli applied in an afferent direction to them.
- 4.4. The “intra-nerve-trunk” neuron decreased its response amplitudes to these stimuli after the third nerve trunk was sectioned in correlation to the response amplitude decrease recorded from the nerve trunk after it was sectioned.
- 5.5. The response amplitude decrease due to denervation implies a nonlinear structure of the earthworm reflex circuits.
- 6.6. The “intramural” neurons are believed to be primary sensory neurons connected to the mechanoreceptors in the setae.
6.
《The International journal of biochemistry》1990,22(7):721-728
- 1.1. In the presence of insulin, 10−5 M 3,3',5-triiodothyronine (T3) treatment for 1/2 hr decreased fatty acid synthesis 35% only in adipocytes from lean rats, whereas at 10−11 M through 10−7M T3 the obese adipocytes had nearly a 20% increase in fatty acid synthesis.
- 2.2. A 2 hr pretreatment of adipocytes with 10−9 and 10−7 M T3 decreased insulin-stimulated fatty acid synthesis by nearly 20% in both lean and obese adipocytes.
- 3.3. In the absence of insulin, the 2 hr pretreatment with 10−9 M T3 resulted in a 45% increase in lean adipocyte fatty acid synthesis, though the obese adipocytes required at least 10−7 M T3 for 2 hr to increase the non-insulin-stimulated fatty acid synthesis by 50%.
- 4.4. At 10−9M T3 concentrations non-insulin-stimulated fatty acid synthesis was increased by 200% in lean adipose tissue explants, but obese adipose expiants were not significantly affected under these conditions.
- 5.5. The addition of 10−9 M T3 plus insulin to the explant media decreased fatty acid synthesis by 35% in both the lean and obese tissues.
- 6.6. The results also imply that the low T3 status of the obese rat may be contributory to the elevated fatty acid synthesis observed in obese adipocytes.
7.
- 1.1. The specific activity of Na-K ATPase was determined from the microsomal preparation of gills dissected from adult Macrobrachium rosenbergii.
- 2.2. Maximal ATPase activity was achieved at a substrate concentration of 0.5 mM ATP.
- 3.3. Optimal enzyme activity was obtained at pH of 7.5.
- 4.4. The Arrhenius plot of Na-K ATPase activity revealed a marked discontinuity at 30°C. “Mg” ATPase activity did not exhibit a marked discontinuity.
- 5.5. The Ea for Na-K ATPase and “Mg” ATPase was 14.6 kCal/mole and 9.31 kCal/mole respectively. Q10 values for Na-K ATPase was 2.34 and for “Mg” ATPase 1.65.
- 6.6. ATPase activity and gill homogenate protein concentration exhibited a linear relationship up to 130 μg protein/ml.
- 7.7. Na-K ATPase activity was inhibited by 10−3 M ouabain. It was equally inhibited by the removal of K+ from the reaction medium.
8.
《Comparative biochemistry and physiology. A, Comparative physiology》1993,104(4):645-648
- 1.1. Homing pigeons, receiving regular flight-training for participation in racing competitions, were flown from their usual release site, 48 km away from “home”.
- 2.2. On their return “home” within 60–80 min, blood samples for the measurement of melatonin were taken within 1–3 min of arrival.
- 3.3. Post-flight circulating levels of melatonin were found to be about 82% higher than those of the resting control pigeons without any change in plasma osmolality.
- 4.4. This daytime increase in circulating levels of melatonin suggests that melatonin, by virtue of its known hypothermic effect of facilitating peripheral heat dissipation, could prevent excessive flight-induced hyperthermia.
- 5.5. It is also suggested that the flight-induced increase in plasma levels of melatonin is consistent with the known analgesic and metabolic effects of the hormone.
9.
- 1.1. The potassium contracture in the anterior byssus retractor muscle of Mytilus edulis relaxed spontaneously, and the relaxation was accelerated by 5-HT (10−6 M), but the contractile activation and inactivation was not affected significantly.
- 2.2. By reducing [Ca]0, the “activation curve” was shifted downward at higher [K]0, and the “inactivation curve” was shifted toward lower [K]0 and the rate of inactivation was increased.
- 3.3. The steady-state inactivation was maintained for at least 2 hr without complete inactivation.
- 4.4. The half-inactivation time was dependent on [K]0, while the half-relaxation time in the contracture induced by conditioning K solutions was not.
10.
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(1):239-244
- 1. The equilibria and kinetics of oxygen binding by blood and hemoglobin from adult and fetal caecilians,Typhlonectes compressicauda, have been measured.
- 2. The oxygen affinity of fetal blood is higher than that of adult blood.
- 3. Electrophoresis of adult and fetal hemoglobins suggests that they may be identical: a major and minor component occurs in each.
- 4. Adult and fetal hemoglobins have identical oxygen equilibria. Stripped hemoglobins have a high oxygen affinity and no Bohr effect between pH 6.5 and 10.0. An “acid”, reversed Bohr effect is present below pH 6.5. The addition of 1 mM ATP reduces the oxygen affinity markedly and produces a moderate, normal Bohr effect.
- 5. The major nucleoside triphosphate in fetal and adult erythrocytes is adenosine triphosphate: about 10% of the nucleoside triphosphates is guanosine triphosphate. Adult erythrocytes contain 3 times as much ATP as do the fetal erythrocytes.
- 6. The fetal to maternal shift in the oxygen equilibrium is mediated entirely by the difference in ATP content of the maternal and fetal red blood cells.
11.
《Comparative biochemistry and physiology. A, Comparative physiology》1984,77(4):539-545
- 1.1. Resting metabolic rates (RMR) below thermoneutrality in adult hyrax acclimated to 26, 15 and 10°C remained unchanged, i.e. thermal conductance (K) remained constant.
- 2.2. Conductance in juveniles decreased with acclimation to lower ambient temperatures (Ta).
- 3.3. Body temperature (Tb) dropped by 3.8°C in adults exposed to Ta of 30 – 5°C. The decrease was constant.
- 4.4. Body temperature fell by 1.5°C in juveniles exposed to Ta of 30 – 20°C but stabilized between 20 and 5°C.
- 5.5. The labile Tb, associated with behavioural strategies and lower than predicted RMR, can be seen as an energy-conserving mechanism of particular importance during winter conditions.
12.
《Comparative biochemistry and physiology. A, Comparative physiology》1982,71(3):469-472
- 1.1. Quick sinusoidal temperature fluctuations (constant average 10°C) cause an increase in metabolism in comparison to an invariable constant ambient temperature of the same dimension.
- 2.2. At the observed mean value of 10°C metabolism is increased by 0.8% per 1 K/hr based on the values of resting metabolic rate (correlation: M = 53.5 + 0.445 Ta, M in J/K g hr, Ta = ambient temperature change in K/hr) and 0.6% based on the values of activity metabolism (M = 70.4 + 0.425 Ta).
- 3.3. The absolute augmentation of metabolism per 1 K/hr is, by comparison, the same for day and night. Its amount is 0.42 and 0.43 J/K g hr respectively.
- 4.4. In the response of metabolism to temperature fluctuations no differences could be found with respect to the amplitude and frequency modifications of temperature.
- 5.5. The increase of energy consumption is probably caused to a greater extent by “overshoot” of the feedback control system in the course of adjusting metabolism to new levels according to the ambient temperature conditions.
- 6.6. Short term ambient temperature changes (i.e. measuring different temperature levels in one night to test basic metabolism vs ambient temperature) cannot produce reasonable values for basic metabolic rate, since these artificially high values reflect the testing procedure.
13.
《Comparative biochemistry and physiology. A, Comparative physiology》1992,101(2):259-267
- 1.1. Changes in glomerular nitration rate (GFR), urine and blood properties and plasma catecholamines of carp were investigated during and following hypoxia.
- 2.2. GFR and urine flow decreased with increased urinary concentrations of bio-components, except protein, in the course of hypoxia.
- 3.3. Decreases in blood pH, and increases in haematocrit value and plasma K+, Ca2+, Mg2+, inorganic phosphate (Pi), ammonia, lactic acid and catecholamines (CAs) were observed as hypoxia progressed.
- 4.4. Increased GFR and urine flow, and higher values for urinary components, except protein, compared with those of the control were found in the initial post-stress stage.
- 5.5. The possible significance of increased plasma CAs in relation to changes in renal function in hypoxic carp is discussed.
14.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1981,68(4):669-678
- 1.1. The biochemical and physiological mechanisms which are involved in anhydrobiotic survival have been reviewed.
- 2.2. The physical state of water within hydrated and dehydrated organisms is discussed in relation to the concepts of “free” and “bound” water and to the “vicinal water network model” of Clegg (1979) Cell Associated Water. Academic Press, New York.
- 3.3. Evidence is presented for the replacement of “bound” water by glycerol in dried embryos of Artemia salina, but the role of high glycerol content in the free-living nematode Aphelenchus avenae has yet to be evaluated.
- 4.4. The adaptive significance of trehalose is shown to lie in the fact that because it is a non-reducing sugar, it will not participate in a “browing” reaction between reduced groups of sugars and free amino groups of dry proteins. Trehalose also inhibits “browning” reactions between reducing sugars and dry proteins.
- 5.5. The effect of dehydration on membrane permeability suggests that dried organisms suffer mostly if placed directly into a revival medium due to leakage through structurally deformed membrane systems.
- 6.6. Glycerol and trehalose may interact with lipid membranes and reduce the amount of leakage.
- 7.7. Damage to membranes caused by lipid peroxidation is discussed.
- 8.8. Results suggest that the role of high lipid contents in nematode anhydrobiotes is essentially that of a food reserve, although the morphological distribution of such lipid may be important in maintaining the spatial distribution of body tissues in the absence of bulk water.
15.
《Comparative biochemistry and physiology. A, Comparative physiology》1982,71(2):255-263
- 1.1. Differential thermal acclimatory responses of maximal catalytic rates (Vmax) of digestive enzymes have been measured in both sexes of Periplaneta americana adapted to 16 and 32°C.
- 2.2. Salivary amylase of females and gastric protease of males exhibit “translational” acclimation, the former showing a “complete” but the latter only a “partial” compensation. The value of Q10 is not altered in the adaptive response.
- 3.3. An alteration of the thermal coefficient is evidenced by the “translational-cum-rotational” compensation of gastric amylolytic activity, with significant warm acclimation but no cold acclimation in both sexes.
- 4.4. Gastric protease of female cockroaches and gastric lipase of both sexes are characterized by the lack of an adaptive compensation to temperature, while salivary amylase of male appears to manifest an “inverse” acclimation.
- 5.5. Sexual dimorphism in the levels of the activities and in the patterns of thermal acclimation of the digestive enzymes is indicated.
16.
《Comparative biochemistry and physiology. A, Comparative physiology》1980,65(4):439-444
- 1.1. The ECG of aquatic Amhystoma tigrinum from the Colorado Rocky Mountains was recorded while the animals submerged and emerged in water. Older larvae and metamorphosed adults were compared.
- 2.2. Free-swimming animals of both types showed slight emergence tachycardia when taking a “gulp” of air.
- 3.3. Preventing access to air for 30 min or more resulted in a slight bradycardia in larvae. Some adults responded with increased, others with decreased, heart rate depending on their level of excitement.
- 4.4. Restraining the animals before forced submergence caused a greater bradycardia than when unrestrained.
- 5.5. Low dissolved oxygen accentuated the cardiac responses of larvae to submergence but not in adults.
- 6.6. Atropine only partially blocked the diving responses of both forms.
- 7.7. The degree of submergence bradycardia seems to be a function of the ability to extract oxygen from water. It probably is not an adaptation to diving in these forms. Instead the submerged heart rate in these predominantly aquatic salamanders may be the “normal” rate with emergence tachycardias for breaths of air.
17.
《Comparative biochemistry and physiology. A, Comparative physiology》1993,104(4):823-830
- 1.1. Indian River male broiler chickens growing from 7 to 28 days of age were fed diets containing 12, 18, 24 and 30% protein + 0 or 1 mg triiodothyronine (T3)/kg of diet to study energetic costs of lipogenesis and the use of various substrates for in vitro lipogenesis.
- 2.2. De novo lipid and CO2 production were determined in the presence of [1-14C]pyruvate, [2-14q]pyruvate, [3-14C]pyruvate, [2-14C]acetate and [U-14C]alanine.
- 3.3. Oxygen consumption was determined in mitochondrial preparations to estimate the energetic costs in expiants synthesizing lipid.
- 4.4. Radiolabeled CO2 derived from [1-14C]pyruvate was used as an estimate of coenzyme A availability in liver expiants. Lipids derived from [2-14C]pyruvate, [2-14C]acetate and [U-14C]alanine estimate relative substrate efficiency.
- 5.5. Labeled CO2 production from [1-14C]pyruvate was greatest in that group fed a 12% protein diet and least in the group fed a 30% protein diet.
- 6.6. In addition, T3 increased CO2 production from [1-14C]pyruvate.
- 7.7. The production of 14CO2 from the second carbon of pyruvate or acetate was increased by T3.
- 8.8. The low-protein diet (12% protein) increased (P <0.05) lipogenesis.
- 9.9. Adding T3 to the diets decreased carbon flux into lipid from all substrates, but increased CO2 production from all substrates without changing stage 3 and 4 respiration rates in mitochondrial preparations.
- 10.10. These observations imply that coenzyme A availability may have regulated de novo lipogenesis in the present study.
- 11.11. It was also concluded that previously noted effects of T3 on intermediary metabolism may involve metabolic pathways that do not involve changes in mitochondrial function.
18.
Functional studies on the single component hemoglobin from an Amazon knife fish,Sternopygus macrurus
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(1):201-205
- 1. The whole blood of the non-air-breathing gymnotid teleost,Sternopygus macrurus, is half-saturated with oxygen at 5.2 mm Hg (apparent value) at 30°C in the absence of CO2. Addition of 5.6% CO2 causes the apparentP50 value to increase over 3-fold.
- 2. The oxygen affinity of the stripped single-component hemoglobin at 20°C increases about 20-fold between pH 5.8 and 8.6 in the absence of ATP. This difference increases to 100-fold in the presence of 1 mM ATP.
- 3. A substantial Root effect is present: the stripped hemoglobin is only 70% saturated with O2 at pH less than 6 when equilibrated with air.
- 4. The value of the Hill coefficient,n, is maximal near pH 7.0–7.5, and approaches 1.0 at high pH. The value is about 1.5 at low pH in the absence of ATP and 1.0 in the presence of 1 mM ATP.
- 5. The O2 dissociation kinetics are heterogeneous at all pH values but most heterogeneous at low pH. The rate increases substantially as the pH decreases.
- 6. The CO combination kinetics as measured by the stopped flow technique are largely homogeneous except at high pH, but the CO combination kinetics after flash photolysis are markedly heterogeneous.
19.
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(1):169-171
- 1.Loricariichthys sp., an air-breathing fish from the Amazon River has one major hemoglobin component.
- 2. Quantitative studies on the kinetics of O2 dissociation and CO combination to the protein were performed by stopped-flow experiments at different pH values and a constant ATP concentration of 1.25 mM.
- 3. The oxygen dissociation shows a simple first order behavior and a strong pH dependence.
- 4. The CO combination kinetics, on the other hand, were homogeneous and fast at higher pH values and slow and clearly autocatalytic at pH values below 7.0.
20.
- 1.1. Ninety-one pairwise comparisons of 14 populations yielded highly significant T2 values for inter-breed differences while four subpopulations of Thoroughbred horses were nearly identical.
- 2.2. Generalized Mahalanobis distance was carried out by comparing simultaneously all 14 populations with respect to 26 variables (phenotypes) contributing most to the discriminant function.
- 3.3. The number of variables could be reduced to 12 phenotypes in final comparisons.
- 4.4. In general the calculated distances agreed with known relationships between horse breeds.
- 5.5. However the obtained distances are thought to be biased due to the nature of selected phenotypes which do not always correspond to “breed-markers”.